OFDM profile generation based on service tiers

Cable modem termination systems (CMTSs) may communicate with cable modems using orthogonal frequency-division multiplexing (OFDM) wherein a channel is divided into subcarriers and the CMTS and cable modem use a particular quadrature amplitude modulation (QAM) order to communicate data over each subcarrier.

The embodiments disclosed herein implement an OFDM profile generator that utilizes service-layer information, such as bandwidth service tier information, in addition to physical layer information to generate optimal OFDM profiles for the CMs supported by a CMTS.

In one implementation a method is provided. The method includes identifying, by a computing device, a plurality of cable modems (CMs) serviced by a cable management termination system (CMTS), each of the CMs being associated with a particular bandwidth service tier of a plurality of bandwidth service tiers. The method further includes grouping, by the computing device, based on the bandwidth service tier with which each CM is associated, the plurality of CMs into a quantity of groups of CMs. The method further includes generating, for each respective CM in each group of CMs, a CM orthogonal frequency division multiplexing (OFDM) profile. The method further includes generating a plurality of group OFDM profiles, each respective group OFDM profile being generated based on the CM OFDM profiles of the CMs in a respective group of CMs and identifying, for each subcarrier of a plurality of subcarriers, a quadrature amplitude modulation (QAM) order.

In another implementation a computing device is provided. The computing device includes a memory and a processor device coupled to the memory. The processor device is operable to identify a plurality of cable modems (CMs) serviced by a cable management termination system (CMTS), each of the CMs being associated with a particular bandwidth service tier of a plurality of bandwidth service tiers. The processor device is further operable to group, based on the bandwidth service tier with which each CM is associated, the plurality of CMs into a quantity of groups of CMs. The processor device is further operable to generate, for each respective CM in each group of CMs, a CM orthogonal frequency division multiplexing (OFDM) profile. The processor device is further operable to generate a plurality of group OFDM profiles, each respective group OFDM profile being generated based on the CM OFDM profiles of the CMs in a respective group of CMs and identifying, for each subcarrier of a plurality of subcarriers, a QAM order.

In another implementation a non-transitory computer-readable storage medium is provided. The non-transitory computer-readable storage medium includes executable instructions to cause a processor device to identify a plurality of cable modems (CMs) serviced by a cable management termination system (CMTS), each of the CMs being associated with a particular bandwidth service tier of a plurality of bandwidth service tiers. The instructions further cause the processor device to group, based on the bandwidth service tier with which each CM is associated, the plurality of CMs into a quantity of groups of CMs. The instructions further cause the processor device to generate, for each respective CM in each group of CMs, a CM orthogonal frequency division multiplexing (OFDM) profile. The instructions further cause the processor device to generate a plurality of group OFDM profiles, each respective group OFDM profile being generated based on the CM OFDM profiles of the CMs in a respective group of CMs and identifying, for each subcarrier of a plurality of subcarriers, a QAM order.

Individuals will appreciate the scope of the disclosure and realize additional aspects thereof after reading the following detailed description of the examples in association with the accompanying drawing figures.

The examples set forth below represent the information to enable individuals to practice the examples and illustrate the best mode of practicing the examples. Upon reading the following description in light of the accompanying drawing figures, individuals will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure and the accompanying claims.

Any flowcharts discussed herein are necessarily discussed in some sequence for purposes of illustration, but unless otherwise explicitly indicated, the examples are not limited to any particular sequence of steps. The use herein of ordinals in conjunction with an element is solely for distinguishing what might otherwise be similar or identical labels, such as “first message” and “second message,” and does not imply an initial occurrence, a quantity, a priority, a type, an importance, or other attribute, unless otherwise stated herein. The term “about” used herein in conjunction with a numeric value means any value that is within a range of ten percent greater than or ten percent less than the numeric value. As used herein and in the claims, the articles “a” and “an” in reference to an element refers to “one or more” of the element unless otherwise explicitly specified. The word “or” as used herein and in the claims is inclusive unless contextually impossible. As an example, the recitation of A or B means A, or B, or both A and B. The word “data” may be used herein in the singular or plural depending on the context. The use of “and/or” between a phrase A and a phrase B, such as “A and/or B” means A alone, B alone, or A and B together.

Cable modem termination systems (CMTSs) may communicate with cable modems (CMs) using the Data Over Cable Service Interface Specification (DOCSIS) telecommunications standard. DOCSIS 3.1 and later utilizes an orthogonal frequency-division multiplexing (OFDM) modulation scheme on the downstream and orthogonal frequency-division multiple access (OFDMA) on the upstream. OFDM divides a channel into multiple subcarriers and the CMTS and CM use a particular quadrature amplitude modulation (QAM) order to communicate data over each subcarrier. QAM is a modulation scheme that allows multiple bits to be communicated in a single constellation. The number of bits communicated in a particular constellation is determined by the particular QAM modulation order (hereinafter “QAM order” for the sake of brevity) that is used by the CMTS and the CM for a particular subcarrier. For example, a 64-QAM order carries 6 bits per constellation (sometimes referred to as a symbol), a 256-QAM order carries 8 bits per constellation, a 1024-QAM order carries 10 bits per constellation, and a 4096-QAM order carries 12 bits per constellation.

The wired media between a CM and a CMTS may be miles long and can be subject to a frequency-selective fading. By using different QAM orders with different subcarriers, a “water-filling” effect can result and the information-theoretical capacity of the channel spectrum can be closely approached. Varying QAM orders per subcarrier is sometimes referred to as the “bit-loading” of OFDM signals.

In DOCSIS a bit-loading plan is referred to as an OFDM profile. Ideally, a separate OFDM profile would be used in the communications between a CMTS and each CM. However, in practice, there are two constraints to OFDM profile management. One constraint is that only a limited number of profiles can be configured on a CMTS. This constraint implies that a group of CMs have to use one OFDM profile that will be sub-optimal to at least some of the group members. Another constraint is that digital modulations only permit certain QAM orders for bit-loading. Often, only 256, 1024 and 4096-QAM orders can be used. In other words, the OFDM profiling can only allocate 8, 10 or 12 bits to a subcarrier.

The embodiments disclosed herein implement an OFDM profile generator that utilizes service-layer information, such as CM bandwidth service tier information, in addition to physical layer information to generate optimal OFDM profiles for the CMs supported by a CMTS. The embodiments herein greatly reduce the time needed to generate a set of OFDM profiles and thus new sets of OFDM profiles can be generated more frequently to address changes in an environment that may impact the conditions of the subcarriers over time. The embodiments herein improve the network capacity of communications between a CMTS and the CMs supported by the CMTS.

is a block diagram of an environmentin which OFDM profile generation based on service tiers can be practiced according to some implementations. The environmentincludes a service provider network, which in turn includes a plurality of CMTSs---Y, a computing deviceand a storage device. The CMTSs---Y may number in the tens, hundreds or thousands. The CMTS-includes a processor deviceand a memory. The CMTS-services (e.g., communicates with), a plurality of CMs---N (generally, CMs). The number of CMsmay be, for example, thousands of CMs, tens of thousands of CMsor hundreds of thousands of CMs.

Similarly, the CMTS-Y includes a processor deviceand a memory. The CMTS-Y services (e.g., communicates with), a plurality of CMs---T (generally, CMs). Again, the number of CMsmay be, for example, thousands of CMs, tens of thousands of CMsor hundreds of thousands of CMs.

The CMTS-also has a limit of four OFDM profiles---, and thus communicates with each CMusing one of the four OFDM profiles---(generally, OFDM profiles). Each OFDM profileidentifies, for each subcarrier of a plurality of subcarriers, a QAM order to be used by the CMTS-and the groups of CMsto which the respective OFDM profilehas been assigned to communicate with one another. An OFDM profilemay identify a particular QAM order for each of thousands of subcarriers that are used by the CMTS-and a CMto communicate with one another. For example, the CM-may be assigned the OFDM profile-, and the CMTS-and the CM-carry out OFDM modulation in accordance with the QAM orders identified in the OFDM profile-. The CM-N may be assigned the OFDM profile-, and the CMTS-and the CM-N carry out OFDM modulation in accordance with the QAM orders identified in the OFDM profile-.

The CMTS-Y has a limit of five OFDM profiles---, and thus communicates with each CMvia one of the five OFDM profiles(generally, OFDM profiles).

The computing deviceincludes a processor deviceand a memory. The computing deviceincludes an OFDM profile generatorthat, as will be discussed in greater detail herein, generates OFDM profiles based in part on a service tier of a CM. The computing deviceincludes or is communicatively coupled to a storage devicethat includes information about each CM in the form of CM profiles---N (generally, CM profiles) through---T (generally, CM profiles). The CM profiles---N correspond to the CMs---N, and the CM profiles---T correspond to the CMs---T. Often a service provider offers different service tiers to its customers, and each service tier may offer a different data transfer speed and have a different subscriber fee. For example, one service tier may offer a 10 Megabit per second (Mbps) download speed for a certain monthly fee, and another service tier may offer a 1 Gigabit per second (Gbps) download speed for a higher monthly fee. For purposes of discussion herein, it will be assumed that the particular service tier associated with the CMsand CMsare identified in the corresponding CM profilesand, respectively, however, it is noted that the identification of the particular service tier with which a CM,is associated may be maintained elsewhere, including, for example, by the CMTSs-and-Y. The CM profilesandmay also identify the particular CMTSthat services the CMsandthat correspond to the CM profilesand.

With this background, an example of OFDM profile generation based on service tiers will now be discussed. In this example the OFDM profile generatorwill determine four OFDM profiles for use by the CMTS-to communicate with the CMs. The OFDM profile generatordetermines a quantityof OFDM profiles that are to be generated for the CMTS-. The quantityof OFDM profiles may be based on a maximum number of OFDM profiles supported by the CMTS-, or may be less than the maximum number of OFDM profiles supported by the CMTS-. The quantityof OFDM profiles may be obtained, for example, by querying the CMTS-, may be a configuration option of the OFDM profile generator, or may be entered by an operator into a user interface of the OFDM profile generator. In this example it will be assumed that the quantityof OFDM profiles is four.

The OFDM profile generatoridentifies the plurality of CMsthat are serviced by the CMTS-. The OFDM profile generatormay determine which CMsare serviced by the CMTS-by querying the CMTS-, by accessing the CM profiles---N through and---T and determining based on the CM profiles---N through---T that the CMsare serviced by the CMTS-, or in any other suitable manner. The OFDM profile generatordetermines, based on the profiles, a number of service tiersthat are associated with the CMs, in this example six.

The OFDM profile generatorgenerates groups of CMsequal to the number of service tiersbased on the bandwidth service tier of each CM, such that each group of CMsis in the same service tier. If the number of service tiers, in this example six, is greater than the OFDM profile quantity, in this example four, then the OFDM profile generatorcombines groups of CMsuntil the number/quantity of groups of CMsmatches the OFDM profile quantity.

The OFDM profile generatorthen generates, for each respective CMin each group of CMs, a CM OFDM profile for the respective CM. The OFDM profile generatorthen generates a plurality of group OFDM profiles, each respective group OFDM profile being generated based on the CM OFDM profiles of the CMsin the respective group.

It is noted that, because the OFDM profile generatoris a component of the computing device, functionality implemented by the OFDM profile generatormay be attributed to the computing devicegenerally. Moreover, in examples where the OFDM profile generatorcomprises software instructions that program the processor deviceto carry out functionality discussed herein, functionality implemented by the OFDM profile generatormay be attributed herein to the processor device.

is a flowchart of a method for OFDM profile generation based on service tiers according to some implementations.will be discussed in conjunction with. The computing devicedetermines the quantityof OFDM profiles to implement on the CMTS-(, block). The computing deviceidentifies the plurality of CMs---N serviced by the CMTS-, each of the CMsbeing associated with a particular bandwidth service tier of a plurality of bandwidth service tiers (, block). The computing devicegroups, based on the bandwidth service tier with which each CMis associated, the plurality of CMsinto a quantity of groups of CMsequal to or fewer than the quantityof OFDM profiles (, block). The computing devicegenerates, for each respective CMin each group of CMs, a CM OFDM profile (, block). The computing devicegenerates a plurality of group OFDM profiles, each respective group OFDM profile being generated based on the CM OFDM profiles of the CMsin a respective group of CMsand identifying, for each subcarrier of a plurality of subcarriers, a QAM order (, block).

is a block diagram illustrating an example implementation of blockofregarding the grouping of CMs serviced by a CMTSwhen the number of bandwidth service tiers associated with the CMs exceeds the quantityof OFDM profiles to be generated for the CMTS. It will be assumed for purposes of illustration that four OFDM group profiles are to be generated for the CMTS-, (e.g., that the quantityof OFDM profiles is four), that the CMTS-services the CMs---N, and that there are nine hundred twenty-five (925) CMs. The OFDM profile generatorinitially generates a plurality of groups---of CMs, each group---of CMscomprising those CMsof the plurality of CMsin a same bandwidth service tier. As discussed above, the OFDM profile generatormay determine the service tier with which a CMis associated based on the CM profiles(), by querying the CMTS-, or in any other suitable manner.

The group-of CMscorresponds to a 10 Mbps service tier, and will be referred to as service tier 1 (ST1). The group-of CMsidentifies 150 CMsthat are in ST1. The group-of CMscorresponds to a 50 Mbps service tier, and will be referred to as service tier 2 (ST2). The group-of CMsidentifies 250 CMsthat are in ST2. The group-of CMscorresponds to a 100 Mbps service tier, and will be referred to as service tier 3 (ST3). The group-of CMsidentifies 75 CMsthat are in ST3. The group-of CMscorresponds to a 500 Mbps service tier, and will be referred to as service tier 4 (ST4). The group-of CMsidentifies 110 CMsthat are in ST4. The group-of CMscorresponds to a 1 Gbps service tier, and will be referred to as service tier 5 (ST5). The group-of CMsidentifies 300 CMsthat are in ST5. The group-of CMscorresponds to a 2 Gbps service tier, and will be referred to as service tier 6 (ST6). The group-of CMsidentifies 40 CMsthat are in ST6.

The OFDM profile generatordetermines that the number of groups---of CMsis greater than the quantityof OFDM profiles, which in this example is four. If the number of groups---of CMswere equal to or less than quantityof OFDM profiles, then the OFDM profile generatorwould end the group combining process because there would be no need to further combine the groups---of CMs. The OFDM profile generatorgenerates a sorted listof the plurality of groups---of CMsbased on a quantity of CMsin each group---of CMs. The sorted listidentifies the groups-,-,-,-,-and-in ascending order of the quantity of CMsin each group.

The OFDM profile generatorcombines two groups of CMsin the list having the least quantity of CMs, in this example the group-of CMsand the group-of CMsto form a new group-Cof CMsthat has count of one hundred fifteen (115) CMs, resulting in groups-C,-,-,-, and-now remaining. The OFDM profile generatorrepeats the sorting and combining processes until the number of groups of CMsis equal to the quantityof OFDM profiles. In this example, the OFDM profile generatorgenerates another sorted listof the plurality of groups-C,-,-,-, and-based on a quantity of CMsin each of the groups-C,-,-,-, and-. The sorted listidentifies the groups-,-C,-,-, and-in ascending order of the quantity of CMsin each group. The OFDM profile generatorcombines two groups in the list having a least quantity of CMs, in this example the group-of CMsand the group-Cof CMsto form a new group-Cof CMsthat has a count of two hundred twenty-five (225) CMs, resulting in groups-C,-,-, and-now remaining. The OFDM profile generatordetermines that the quantity of groups-C,-,-, and-is equal to the quantityof OFDM profiles that are to be generated for the CMTS-, and thus ends the group combining process.

is a flowchart of a method for grouping of CMs serviced by a CMTSwhen the number of bandwidth service tiers associated with the CMs exceed the quantity of OFDM profiles to be generated for a CMTS.will be discussed in conjunction with. The OFDM profile generatorgenerates the plurality of groups---of CMs, each group of CMscomprising those CMsof the plurality of CMsin a same bandwidth service tier (, step). The OFDM profile generatordetermines that the number of groups---of CMsis greater than the quantityof OFDM profiles (, step).

The OFDM profile generatorgenerates the sorted listof the plurality of groups-,-,-,-,-and-of CMsbased on a quantity of CMsin each group of CMs(, step). The OFDM profile generatorcombines the two groups-and-in the listhaving a least quantity of CMsto form the new group-Cof CMs(, step). The OFDM profile generatorrepeats steps,anduntil at stepthe number of groups of CMsis not greater than the quantityof OFDM profiles.

is a block diagram illustrating an example implementation of blockofregarding the generation of a group OFDM profile based on the CM OFDM profiles of a group of CMs in a group of CMs.will discuss the generation of a group OFDM profilebased on the group-Cof CMsgenerated in accordance with. Additional group OFDM profiles would be generated in a similar manner for the groups-,-and-illustrated in.

The OFDM profile generatorinitially generates a corresponding CM OFDM profile---(generally, CM OFDM profiles) for each of the two hundred twenty five CMsin the group-Cof CMs. The OFDM profile generator, for each respective CMin the group-Cof CMs, determines, for each respective subcarrier of a plurality of subcarriers, a QAM order for the respective subcarrier based at least in part on a signal-to-noise ratio (SNR) for the respective subcarrier for the respective CM. The number of subcarriers can be in the tens, hundreds or thousands. In this example, it will be assumed that the group OFDM profiles identify QAM orders for 2000 subcarriers. The OFDM profile generatormay obtain the SNR for the respective subcarrier for the respective CMin any suitable manner. In some implementations, the CMTS-maintains CM channel quality (CQ) informationfor each of the CMsserviced by the CMTS-. Such CM channel quality (CQ) informationmay derived based on information provided by the CMs, and may include any suitable metrics, including SNR information, that quantifies the conditions of each subcarrier for each CM. Such information may be stored by the CMTS-periodically in a location known to the OFDM profile generator, or the OFDM profile generatormay query the CMTS-for such information. The determination of a QAM order for a subcarrier based at least in part on the SNR information will be discussed in greater detail below. In some implementations, the CMsrelatively continuously determine the SNR associated with each subcarrier and report the SNRs to the CMTS-.

As an example, for the CM OFDM profile-, the OFDM profile generatordetermines a QAM order-, QAM 256, for a subcarrier 1 (e.g., “SC1:8”). It is noted that inthe QAM order is designated by the number of bits per QAM constellation, wherein 256-QAM is 8 bits, 1024-QAM is 10 bits, and 4096-QAM is 12 bits. The OFDM profile generatordetermines a QAM order-, QAM 1024, for a subcarrier 2 (e.g., “SC2:10”), a QAM order-, QAM 1024, for a subcarrier 3 (e.g., “SC3:12”), and a QAM order-, QAM 256 for a subcarrier(e.g., “SC2000:8”). The OFDM profile generatorsimilarly determines QAM orders for each of the 2000 subcarriers for each of the 225 CMsin the group-Cof CMs.

In one implementation, a CM OFDM profile can be generated in accordance with the following steps. For purposes of discussion, the SNR for CM m on subcarrier i will be denoted as γ. γ=0(dB) is defined for the current system performance margin, and Γ for the SNR Gap. The performance margin is the amount of extra SNR above the level required for the OFDM signals to be received with a tolerable bit-error-rate. This margin provides room to the CM to accommodate unaccounted interferences and impulse noise. SNR Gap Γ is a system parameter that is determined by the error-correcting code used in the modulation and coding method used to define the format of the OFDM signal and gives the additional tolerance of noise of the transmitter and receiver in the CMTS and the CM compared to that of a parity system without the error-correcting code. The term “parity system” in this context refers to a CMTS and CM using the same modulation and coding method but without error-correcting code.

The value of Γ can be obtained empirically or by calculations for the error-correcting code. γis the additional noise tolerance when a particular modulation order is chosen for bit-loading. In calculating the optimal profile for a CM, the optimization target is to maximize this γ=0(dB).

Let iteration=0 initially for an iteration counter.

Step a.

After determining the CM OFDM profiles---, the OFDM profile generatorgenerates the group OFDM profilebased on the plurality of CM OFDM profiles---. In one implementation, the OFDM profile generator, for each respective subcarrier of the 2000 subcarriers, determines a most occurring QAM order that is identified for the respective subcarrier in the CM OFDM profiles. The OFDM profile generatorthen selects the most occurring QAM order as the QAM order for the respective subcarrier in the group OFDM profile.

For example, the OFDM profile generatordetermines that the most occurring QAM order for subcarrier 1 in the CM OFDM profiles---is QAM 1024, and thus stores a QAM order-, QAM 1024, for subcarrier 1 in the group OFDM profile. The OFDM profile generatordetermines that the most occurring QAM order for subcarrier 2 in the CM OFDM profiles---is QAM 256, and thus stores a QAM order-, QAM 256, for subcarrier 2 in the group OFDM profile. The OFDM profile generatordetermines that the most occurring QAM order for subcarrier 3 in the CM OFDM profiles---is QAM 4096, and thus stores a QAM order-, QAM 4096, for subcarrier 3 in the group OFDM profile. The OFDM profile generatordetermines that the most occurring QAM order for subcarrierin the CM OFDM profiles---is QAM 1024, and thus stores a QAM order-, QAM 1024, for subcarrierin the group OFDM profile.

The OFDM profile generatorrepeats this process for each of the groups-,-and-illustrated in, to form corresponding group OFDM profiles for the groups-,-and-. The OFDM profile generatormay then communicate the four group OFDM profiles to the CMTS-for use in communicating with the CMs.

is a flowchart of a method for generating a group OFDM profile based on the CM OFDM profiles of a group of CMs according to one implementation.will be discussed in conjunction with. The OFDM profile generatorselects the first CMin the group-Cof CMs(, step). The OFDM profile generatorstarts with the first subcarrier, and accesses the CM channel quality informationthat corresponds to that subcarrier for that CM(, steps,). The OFDM profile generatordetermines a particular QAM order for that subcarrier for that CMbased at least in part on the CM channel quality information(, step). The OFDM profile generatorstores the QAM order in the CM OFDM profile (, step). The OFDM profile generatordetermines whether there are additional subcarriers for which a QAM order needs to be determined (, step). If so, the OFDM profile generatorincrements to the next subcarrier, and repeats the process (steps,-) until a QAM order has been determined for each subcarrier. If at stepthe OFDM profile generatordetermines that a QAM order has been determined for each subcarrier, the OFDM profile generatordetermines that the CM OFDM profile is complete (step). The OFDM profile generatordetermines if there are additional CMsin the group-Cof CMsfor which a CM OFDM profile is to be generated (, step). If so, the OFDM profile generatordetermines the next CMin the group-Cof CMs, and repeats the process (steps,-) until a CM OFDM profile has been generated for each CMin the group-Cof CMs.

If at stepthe OFDM profile generatorhas generated a CM OFDM profile for each CMin the group-Cof CMs, the OFDM profile generatorstarts with the first subcarrier and iterates through each CM OFDM profile to determine a most occurring QAM order of the plurality of QAM orders that is identified for the respective subcarrier in the CM OFDM profiles (steps,). The OFDM profile generatormay, for example, sum, for each QAM order identified in any CM OFDM profile for the first subcarrier, the number of CM OFDM profiles that contain that QAM order for the first subcarrier.

The OFDM profile generatorselects the most occurring QAM order (e.g., the QAM order identified in the greatest number of CM OFDM profiles) as the QAM order for the first subcarrier in the group OFDM (, step). The OFDM profile generatorstores the most occurring QAM order as the QAM order for the first subcarrier in the group OFDM profile(, step). The OFDM profile generatordetermines whether there are additional subcarriers for which a QAM order needs to be determined (, step). If so, the OFDM profile generatorincrements to the next subcarrier, and repeats the process (steps,-) until a QAM order has been determined for each subcarrier. If at stepthe OFDM profile generatordetermines that a QAM order has been determined for each subcarrier, the OFDM profile generatordetermines that the group OFDM profile is complete (step). The OFDM profile generatormay repeat the steps discussed herein for each of the other groups-,-and-to generate corresponding group OFDM profiles.

is a block diagram of the computing devicesuitable for implementing examples according to one example. The computing devicemay comprise any computing or electronic device capable of including firmware, hardware, and/or executing software instructions to implement the functionality described herein, such as a computer server, a desktop computing device, a laptop computing device, or the like. The computing deviceincludes the processor device, the system memory, and a system bus. The system busprovides an interface for system components including, but not limited to, the system memoryand the processor device. The processor devicecan be any commercially available or proprietary processor.

The system busmay be any of several types of bus structures that may further interconnect to a memory bus (with or without a memory controller), a peripheral bus, and/or a local bus using any of a variety of commercially available bus architectures. The system memorymay include non-volatile memory(e.g., read-only memory (ROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.), and volatile memory(e.g., random-access memory (RAM)). A basic input/output system (BIOS)may be stored in the non-volatile memoryand can include the basic routines that help to transfer information between elements within the computing device. The volatile memorymay also include a high-speed RAM, such as static RAM, for caching data.

The computing devicemay further include or be coupled to a non-transitory computer-readable storage medium such as a storage device, which may comprise, for example, an internal or external hard disk drive (HDD) (e.g., enhanced integrated drive electronics (EIDE) or serial advanced technology attachment (SATA)), HDD (e.g., EIDE or SATA) for storage, flash memory, or the like. The storage deviceand other drives associated with computer-readable media and computer-usable media may provide non-volatile storage of data, data structures, computer-executable instructions, and the like.